Private Sub BtnTransparenteFarbeEntfernen_Click(ByVal sender As _
      System.Object, ByVal e As System.EventArgs) Handles _
      BtnTransparenteFarbeEntfernen.Click
        If LangsamesTransperentVerfahren.Checked = false Then
            GoTo BtnTransparenteFarbeEntfernen_Click_Langsam
        End If
        Cursor = Cursors.WaitCursor
 
        Dim Diff As Integer = Farbabweichung.Text
        Dim A As Integer = AktuelleFarbeA.Text
        Dim R As Integer = AktuelleFarbeR.Text
        Dim G As Integer = AktuelleFarbeG.Text
        Dim B As Integer = AktuelleFarbeB.Text
        Dim RN As Integer
        Dim GN As Integer
        Dim BN As Integer
        Dim z As Integer
        Dim myBitmap As New Bitmap(BildAnzeigeNeu.Image)
 
        For z = Diff * -1 To Diff
            RN = R + z
            GN = G + z
            BN = B + z
            If RN < 0 Then
                RN = 0
            End If
            If RN > 255 Then
                RN = 255
            End If
 
            If GN < 0 Then
                GN = 0
            End If
            If GN > 255 Then
                GN = 255
            End If
 
            If BN < 0 Then
                BN = 0
            End If
            If BN > 255 Then
                BN = 255
            End If
            '       MsgBox(z & "  RN " & RN & "  GN " & GN & "  BN " & BN)
            'PictureBox1.Image = ReplaceColor(Image.FromFile(Label1.Text), 
            ' Color.FromArgb(255, RN, GN, BN), Color.Aquamarine)
            'PictureBox1.Image = ReplaceColor(PictureBox1.Image, Color.FromArgb( 
            ' 255, RN, GN, BN), Color.Aquamarine)
            myBitmap = ReplaceColor(myBitmap, Color.FromArgb(A, RN, GN, BN), _
              Color.FromArgb(0, 0, 0, 0))
        Next
        BildAnzeigeNeu.Image = myBitmap
 
        Cursor = Cursors.Arrow
 
        Exit Sub
BtnTransparenteFarbeEntfernen_Click_Langsam:
        Dim BMP As Bitmap = BildAnzeigeNeu.Image
        'Dim VAktuelleFarbeA As Integer
        'Dim VAktuelleFarbeR As Integer
        'Dim VAktuelleFarbeG As Integer
        'Dim VAktuelleFarbeB As Integer
        Dim AktuellA As Integer
        Dim AktuellR As Integer
        Dim AktuellG As Integer
        Dim AktuellB As Integer
 
        Cursor = Cursors.WaitCursor
 
        ' Color [A=255, R=31, G=28, B=22]
        'AktuelleFarbeA = Mid(AktuelleFarbe.Text, InStr(1, AktuelleFarbe.Text, 
        ' "A=") + 2, 3)
        'AktuelleFarbeR = Mid(AktuelleFarbe.Text, InStr(1, AktuelleFarbe.Text, 
        ' "R=") + 2, 3)
        'AktuelleFarbeG = Mid(AktuelleFarbe.Text, InStr(1, AktuelleFarbe.Text, 
        ' "G=") + 2, 3)
        'AktuelleFarbeB = Val(Mid(AktuelleFarbe.Text, InStr(1, 
        ' AktuelleFarbe.Text, "B=") + 2, 3))
 
        'VAktuelleFarbeA = AktuelleFarbeA.Text
        'VAktuelleFarbeR = AktuelleFarbeR.Text
        'VAktuelleFarbeG = AktuelleFarbeG.Text
        'VAktuelleFarbeB = AktuelleFarbeB.Text
 
        ' Wenn die gewählte Farbe schon Weiss ist, dann die Sub verlassen
        If AktuelleFarbeA.Text + AktuelleFarbeR.Text + AktuelleFarbeG.Text + _
          AktuelleFarbeB.Text = 0 Then
            Cursor = Cursors.Arrow
            Exit Sub
        End If

        '  MsgBox(BMP.Width & "   " & BMP.Height)
        For x As Integer = 0 To BMP.Width - 1 ' Val(Me.Breite.Text) - 1 '  Val( _
          Me.XPos.Text) + 1 To Val(Me.Breite.Text) - 1
            For y As Integer = 0 To BMP.Height - 1 ' Val(Me.Höhe.Text) - 1 'Val( _
            Me.YPos.Text) + 1 To Val(Me.Höhe.Text) - 1
                'MsgBox(BMP.GetPixel(x, y).ToString & "    " & 
                ' Me.AktuelleFarbe.Text)
                BearbeiteteAktuelleFarbe.Text = BMP.GetPixel(x, y).ToString
                AktuellA = Mid(BearbeiteteAktuelleFarbe.Text, InStr(1, _
                  BearbeiteteAktuelleFarbe.Text, "A=") + 2, 3)
                AktuellR = Mid(BearbeiteteAktuelleFarbe.Text, InStr(1, _
                BearbeiteteAktuelleFarbe.Text, "R=") + 2, 3)
                AktuellG = Mid(BearbeiteteAktuelleFarbe.Text, InStr(1, _
                BearbeiteteAktuelleFarbe.Text, "G=") + 2, 3)
                AktuellB = Val(Mid(BearbeiteteAktuelleFarbe.Text, InStr(1, _
                BearbeiteteAktuelleFarbe.Text, "B=") + 2, 3))
 
                ' If BMP.GetPixel(x, y).ToString = Me.AktuelleFarbe.Text Then 
                ' 'Or BMP.GetPixel(x, y).ToString = "Color [A=255, R=252," & _
                "G=255, B=255]" Or BMP.GetPixel(x, y).A = 0 Or BMP.GetPixel(x, _
                y).R > 250 Or BMP.GetPixel(x, y).G > 250 Or BMP.GetPixel( _
                x, y).B > 250 Then
                ' If AktuelleFarbeA=AktuellA and AktuelleFarbeR=AktuellR and 
                ' AktuelleFarbeG=AktuellG and AktuelleFarbeB=AktuellB and 
                If Abweichnung_Farbwert(AktuellR, AktuelleFarbeR.Text, "R") = _
                  True And Abweichnung_Farbwert(AktuellG, AktuelleFarbeG.Text, _
                  "G") = True And Abweichnung_Farbwert(AktuellB, _
                  AktuelleFarbeB.Text, "B") = True Then
 
                    '    If AktuelleFarbeR = AktuellR And AktuelleFarbeG = 
                    ' AktuellG And AktuelleFarbeB = AktuellB Then
                    BMP.SetPixel(x, y, Color.Transparent)
 
                End If
            Next
            'MsgBox("")
        Next
        BildAnzeigeNeu.Image = BMP
        BildAnzeigeNeu.Refresh()
 
        Cursor = Cursors.Arrow
    End Sub
 
    Public Function ReplaceColor(ByVal oBitmap As Image, ByVal OldColor As _
      Color, ByVal NewColor As Color) As Image
 
        ' ColorMap mit Zuweisung der zu konvertierenden 
        ' Farben(erstellen)
        Dim oMap(0) As ColorMap
        oMap(0) = New ColorMap
        With oMap(0)
            .OldColor = OldColor
            .NewColor = NewColor
        End With
 
        ' ImageAttributes-Objekt mit Farbanpassung erstellen
        Dim oAttr As New ImageAttributes
        oAttr.SetRemapTable(oMap)
 
        ' Neues Image-Objektop erstellen
        Dim imgWidth As Integer = oBitmap.Width
        Dim imgHeight As Integer = oBitmap.Height
        Dim oImage As Image = Image.FromHbitmap(New Bitmap(imgWidth, _
          imgHeight).GetHbitmap)
 
        Using g As Graphics = Graphics.FromImage(oImage)
            g.DrawImage(oBitmap, New Rectangle(0, 0, imgWidth, imgHeight), 0, _
              0, imgWidth, imgHeight, GraphicsUnit.Pixel, oAttr)
        End Using
 
        ' neues Bild zurückgeben
        Return oImage
    End Function
 
 Function Abweichnung_Farbwert(ByVal Farbwert1 As Integer, ByVal Farbwert2 As _
   Integer, ByVal Farbe As String) As Boolean
        Abweichnung_Farbwert = False
        Dim DIff As Integer
        DIff = System.Math.Abs(Farbwert1 - Farbwert2)
        Select Case Farbe
            Case "A"
                If DIff <= My.Settings.FarbAbweichungA Then ' DIff >= 
                ' My.Settings.AbweichungA * -1 And DIff <= 
                ' My.Settings.AbweichungA Then
                    Abweichnung_Farbwert = True
                End If
            Case "R"
                If DIff <= My.Settings.FarbAbweichungR Then 'DIff >= 
                ' My.Settings.AbweichungR * -1 And DIff <= 
                ' My.Settings.AbweichungR Then
                    Abweichnung_Farbwert = True
                End If
            Case "G"
                If DIff <= My.Settings.FarbAbweichungG Then ' DIff >= 
                ' My.Settings.AbweichungG * -1 And DIff <= 
                ' My.Settings.AbweichungG Then
                    Abweichnung_Farbwert = True
                End If
            Case "B"
                If DIff <= My.Settings.FarbAbweichungB Then 'DIff >= 
                ' My.Settings.AbweichungB * -1 And DIff <= 
                ' My.Settings.AbweichungB Then
                    Abweichnung_Farbwert = True
                End If
        End Select
    End Function

private Bitmap SetTransparent(Bitmap vectorImage)
{
    //ist bei mir immer der Hintergrund, musst du für dich anpassen!
    Color c = vectorImage.GetPixel(10, 10);
 
    vectorImage.MakeTransparent(c);
    return vectorImage;
}

Gruß
Christoph

Gruß
Christoph

 
Public Class Form3
    Private Sub BildanzeigeNeu_MouseClick(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.MouseEventArgs) Handles BildanzeigeNeu.MouseClick
        BildanzeigeNeu.Image = aSetTransparent(BildanzeigeNeu.Image)
    End Sub
 
    Private Sub BildanzeigeNeu_MouseMove(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.MouseEventArgs) Handles BildanzeigeNeu.MouseMove
        Me.XMouse.Text = e.X
        Me.YMouse.Text = e.Y
 
        If Me.XMouse.Text > BildanzeigeNeu.Width Or Me.YMouse.Text > _
          BildanzeigeNeu.Height Then Exit Sub
        If IsNothing(BildanzeigeNeu.Image) Then Exit Sub
 
        Dim myBitmap As New Bitmap(BildanzeigeNeu.Image)
        On Error Resume Next
        Dim pixelColor As Color = myBitmap.GetPixel(Val(Me.XMouse.Text), Val( _
          Me.YMouse.Text))
 
        AktuelleFarbeA.Text = pixelColor.A
        AktuelleFarbeR.Text = pixelColor.R
        AktuelleFarbeG.Text = pixelColor.G
        AktuelleFarbeB.Text = pixelColor.B
 
        Call BildanzeigeNeu.Refresh()
 
    End Sub
 
    Private Sub BildanzeigeNeu_Paint(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.PaintEventArgs) Handles BildanzeigeNeu.Paint
 
        ' Fadenkreuz zeichnen
        Dim fk As Graphics = e.Graphics
 
        Dim Ypoints As Point() = {New Point(0, Val(YMouse.Text)), New Point( _
          Me.BildanzeigeNeu.Width, Val(Me.YMouse.Text))}
        fk.DrawLines(Pens.Black, Ypoints)
 
        Dim Xpoints As Point() = {New Point(Val(XMouse.Text), 0), New Point(Val( _
          Me.XMouse.Text), Me.BildanzeigeNeu.Height)}
        fk.DrawLines(Pens.Black, Xpoints)
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        OpenFileDialog1.Filter = "JPG|*.jpg|Bitmap|*.bmp"
        If OpenFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
            BildanzeigeNeu.Image = Image.FromFile(OpenFileDialog1.FileName)
 
        End If
 
    End Sub
 
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button3.Click
        BildanzeigeNeu.Image = SetTransparent(BildanzeigeNeu.Image)
    End Sub
 
    Private Function SetTransparent(ByVal vectorImage As Bitmap) As Bitmap
        Dim Diff As Integer = Farbabweichung.Text
        Dim A As Integer = AktuelleFarbeA.Text
        Dim R As Integer = AktuelleFarbeR.Text
        Dim G As Integer = AktuelleFarbeG.Text
        Dim B As Integer = AktuelleFarbeB.Text
        Dim RN As Integer
        Dim GN As Integer
        Dim BN As Integer
        Dim z As Integer
 
        For z = Diff * -1 To Diff
            RN = R + z
            GN = G + z
            BN = B + z
            If RN < 0 Then
                RN = 0
            End If
            If RN > 255 Then
                RN = 255
            End If
 
            If GN < 0 Then
                GN = 0
            End If
            If GN > 255 Then
                GN = 255
            End If
 
            If BN < 0 Then
                BN = 0
            End If
            If BN > 255 Then
                BN = 255
            End If
            'MsgBox(z & "  RN " & RN & "  GN " & GN & "  BN " & BN)
            vectorImage.MakeTransparent(Color.FromArgb(A, RN, GN, BN))
        Next
        Return vectorImage
    End Function
 
End Class

Gruß
Christoph

________
Alle Angaben ohne Gewähr. Keine Haftung für Vorschläge, Tipps oder sonstige Hilfe, falls es schiefgeht, nur Zeit verschwendet oder man sonst nicht zufrieden ist

Imports System.Drawing.Imaging
Imports System.Runtime.InteropServices
 
Public Class Form5
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
 
        OpenFileDialog1.Filter = "JPG (*.JPG)|*.jpg|GIF (*.gif)|*.gif|Alle|*.*"
        OpenFileDialog1.ShowDialog()
        BildAnzeigeNeu.Image = Image.FromFile(OpenFileDialog1.FileName)
 
    End Sub
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button2.Click
        PictureBox1.Image = BildAnzeigeNeu.Image
 
        PictureBox1.Refresh()
 
    End Sub
 
    Private Sub PictureBox1_Paint(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
 
        If IsNothing(BildAnzeigeNeu.Image) Then Exit Sub
 
        Dim Diff As Byte = Farbabweichung.Text
        Dim A As Byte = AktuelleFarbeA.Text
        Dim R As Byte = AktuelleFarbeR.Text
        Dim G As Byte = AktuelleFarbeG.Text
        Dim B As Byte = AktuelleFarbeB.Text
        Dim RN As Byte
        Dim GN As Byte
        Dim BN As Byte
        Dim z As Integer
 
        For z = Diff * -1 To Diff
 
            Dim bmp As Bitmap = New Bitmap(BildAnzeigeNeu.Image)
 
            Dim Graph As Graphics = Graphics.FromImage(bmp)
 
            RN = R + z
            GN = G + z
            BN = B + z
            If RN < 0 Then
                RN = 0
            End If
            If RN > 255 Then
                RN = 255
            End If
 
            If GN < 0 Then
                GN = 0
            End If
            If GN > 255 Then
                GN = 255
            End If
 
            If BN < 0 Then
                BN = 0
            End If
            If BN > 255 Then
                BN = 255
            End If
 
            Dim attr As New ImageAttributes
 
             Dim c As Color = Color.FromArgb(0, RN, GN, BN)
 
            ' Set the transparency color key based on the upper-left pixel 
            ' of the image.
            ' Uncomment the following line to make all black pixels transparent:
            '  attr.SetColorKey(bmp.GetPixel(0, 0), bmp.GetPixel(0, 0))
 
            ' Set the transparency color key based on a specified value.
            ' Uncomment the following line to make all red pixels transparent:
            attr.SetColorKey(c, c)
 
            ' Draw the image using the image attributes.
            PictureBox1.Image = Nothing
            Dim dstRect As New Rectangle(0, 0, bmp.Width, bmp.Height)
            e.Graphics.DrawImage(bmp, dstRect, 0, 0, bmp.Width, bmp.Height, _
              GraphicsUnit.Pixel, attr)
         Next
    End Sub
 
    Private Sub Form5_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        AktuelleFarbeA.Text = 255
        AktuelleFarbeR.Text = 220
        AktuelleFarbeG.Text = 241
        AktuelleFarbeB.Text = 236
        Farbabweichung.Text = 0
        'invert()
    End Sub
end class